Two theorems are proved. They are with principal significance in functional analysis, for they imply some well known theorems, such as the open mapping theorem, the closed graph theorem and the Banach Steinhaus theo...Two theorems are proved. They are with principal significance in functional analysis, for they imply some well known theorems, such as the open mapping theorem, the closed graph theorem and the Banach Steinhaus theorem.展开更多
A coupled system of three nonlinear oscillators with symmetric couplings is studied.It turns out that there exists a reduced variational equation to the in phase periodic solution of such a coupled system.By the symme...A coupled system of three nonlinear oscillators with symmetric couplings is studied.It turns out that there exists a reduced variational equation to the in phase periodic solution of such a coupled system.By the symmetry one establishes a structural property for the monodromy matrix of the reduced variational equation,which simplifies the computation of multipliers to a great extent.As an application of the above results,a coupled system of three Poincare oscillators is discussed as well.展开更多
In this paper, we study a non-autonomous ratio-dependent predator-prey model with predator＇s harvest. By means of the coincidence degree theory, we establish sufficient conditions for the existence of at least two po...In this paper, we study a non-autonomous ratio-dependent predator-prey model with predator＇s harvest. By means of the coincidence degree theory, we establish sufficient conditions for the existence of at least two positive periodic solutions of this model.展开更多
文摘Two theorems are proved. They are with principal significance in functional analysis, for they imply some well known theorems, such as the open mapping theorem, the closed graph theorem and the Banach Steinhaus theorem.
文摘A coupled system of three nonlinear oscillators with symmetric couplings is studied.It turns out that there exists a reduced variational equation to the in phase periodic solution of such a coupled system.By the symmetry one establishes a structural property for the monodromy matrix of the reduced variational equation,which simplifies the computation of multipliers to a great extent.As an application of the above results,a coupled system of three Poincare oscillators is discussed as well.
基金the Scientific Research Foundation of the Doctor Department of Hubei University of Technology
文摘In this paper, we study a non-autonomous ratio-dependent predator-prey model with predator＇s harvest. By means of the coincidence degree theory, we establish sufficient conditions for the existence of at least two positive periodic solutions of this model.
